Pneumatic sand-ramming machine



1 D. J. CAMPBELL PNEUMATIC SAND RAMMING MACHINE Filc] Nov.

10 1919 6 Sheets-Sheet 1 a 4 0 w o a 2 w 9' .M/ Q w ww a 3 h 2 o a/d any vigil filo/"nay April 29 1924. 1,492,352

D. .1. CAMPBELL PNEUMATIC SAND RAMMING MACHINE Filed Nov. 10 1919 6 Sheets-Sheet 2 April 29, 1924.

D. J. CAMPBELL PNEUMATIC SAND RAMMING MACHINE 6 Sheets-Sheet 5 Filed Nov. 10 1919 MM N% April 29, 2 1,492,352

1 D. J. CAMPBELL PNEUMATIC SAND RAMMING MACHINE Filed Nov] 10 1919 6 Sheets-Sheet 4 KZ5O6WM% D. J. CAMPBELL PNEUMATIC SAND RAMMING MACHINE Filed Nov. 10

1-919 6 Sheets-Sheet e aim/w Patented Apr. 29, 1924.

DONALD J. CBELL, O'F MUSKEGON HEIGHTS, MICHIGAN.

PNEUMATIC sann-nammme 0mm Application filed November 10, 1919. Serial No. 336,832.

To all whom it may concern:

Be it known that I, I)ONALD J. CAMPBELL, a citizen of the United States of America, residing at Muskegon Heights, in the county of Muskegonand State of Michigan, have invented" certain new and useful Improvements in Pneumatic Sand-Hamming Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertainsto make and use the same.

This invention relates to machines adapted to be operated soas to take small quantities of sand and pneumatically eject the sameinto a flaskaround-a mould. Usually the ramnungof sand 1n flasks in the opera- .tion of molding has been done manually.

In my invention it is contemplated that the moulding sand shall be thrown into the flask with force suflicient to pack or ram the sand to the necessary degreeand that the force of throwing the sand be supplied by compressed air which is applied periodically but at -very close intervals so that successive small quantities of sand are rapidly thrown into the flask or practically forced thereinto by the force of compressed air. A further object of the invention is to providea machine of this character which has a large range of movement whereby the same may be directed to different parts of the flask or may be used with flasks differently positioned or of different sizes. Various other objects and purposes of the invention consists in a novel construction andarrangementof parts-for bringing the sand into proper position with respect to the compressed air nozzle so that the sameshall be in position to receive the force of the air for purposes of ejecting the same; in means for controlling the passage of sand to the machine, and in many other novel features of construction-and arrangement of parts for the practical and effective attainment of the ends for which the machine is designed, allof'which will appear fully and in detail in the following description taken in connection with the accompanying drawings. in which;

Fig. 1 is a side elevation of the complete machine.

Fig. 2 is a side elevation enlarged, over that shown in Fig. 1 of the sand receiving and ejecting mechanism.

Fig. 3 is an enlarged fragmentary vertical section through a detail of mechanism-having to do with the periodic operation of the a1r emmission.

Fig. 4: is a central vertical section taken through the construction shown in Fig. 2.

Fig. 5 is an enlarged section of the lower part of the sand receiving casing and the conveyor and the pneumatic air means located therein.

Fig. 6 is a section taken substantially on the line 66 of Fig. 2.

Fig. 7 is an elevation of the screw conveyor forming a part of the machine.

Fig. 8 is a plan View thereof.

Figs.- 9 and 10 are fragmentary sections and elevation taken substantially on the lines 9-9 and 10-10 of Fig. 8.

Fig.11 is a fragmentary side elevation of -is delivered to the screw;

Fig. 12 is a plan of the carriage and'sup- Fig. 13 is a view similar to Fig. 4 illustrating a-modification in construction.

Fig. 14: is a side .elevatiofi'thereof, the covering member being removed.

Fig. 15 is a fragmentary vertical section somewhat enlarged illustrating the mechanism used for operating the air valve; and

Figs. 16 and 17 are horizontal sections taken respectively on the lines 1616 and 1717 of Fig. 15.

Like reference characters refer to like parts in the difl'erent parts ofthe drawings.

In the construction a support, including vertical posts 1 attached at their lower ends to a suitable base 2 and with diagonal braces '3 connected to the. posts 1 by suitable ties 4 and 5, is provided, the lower ends of the braces 3 being connected to a sand receiving receptacle 6 and at theirupper ends to a hopper 7 to which the sand is delivered. An endless conveyor 8.is mounted to run around a wheel 9 mounted on a suitable horizontal shaft at the upper end ofthe support and a similar wheel Within the sand receptacle 6, this conveyor being equipped with a plurality of sand cups 10 so that when the conveyor is operated the sand is carried from the receptacle 6 to the hopper 7. Said hopper 7 has an outlet at 11 for the sand to pass. from the hopper to a second hopper 12.

- the upper part of the conveying screw illus- ,port therefor which carries the mechanism.

A return conduit 13 is disposed between the hopper 7 and the sand receptacle 6. An arm 14 is mounted on the hopper 7 and is adapted to be moved by manual operation of a downwardly extending rod 15, it being designed that operation of this arm 14 is to control the delivery of} the sandeither to the second hopper 12 or to the return conduit 13. The specific means for effecting this control is not novel, forms no part of the invention, and is not specifically shown and described.

The second hopper 12 is secured at the upper end of a post 16 which is mounted in front of the posts 1 on upper and lower brackets 17, being mounted so as to turn about a vertical axis. A bracket comprising two upper horizontal arms 18 and diagonal downwardly extending braces 19 is mounted on the post 16 andmay be (raised or lowered by turning a screw 20 connected with the part 19 and operated by a handle 21 as shown-in Fig. 1. The. arms 18 of the bracket are supports for a carriage, hereafter described, on which the pneumatic sand ramming machine is mounted and to which sand is delivered from a receptacle 22 into which the sand passes from the second hopper 12 through an outlet pipe 23 as shown.

The carriage 24 is mounted on rollers 25 so as to move back and forth over the hrms 18. A ring 27 is pivotally mounted on a horizontal axis between the arms 18 and a platform 27 is pivotally mounted within the ring 27, the axes of the'pivots 28 and 28 of the ring and platform being at right angles to each other so that the platform and attached mechanism thereon have a universal movement with respect to the supporting arms 18. One of the carriage rollers is provided with a pinion 25 which engages with a rack 26. The shaft 30 of the roller on which pinion 25 is mounted is extended slightly and on it a wheel 31 is fixed, around which an endless chain 32 passes, the same extending downwardly so as to be within reach of the operator whereby by pulling on this chain the carriage may be moved to different positions with respect to the supporting arms 18. The platform 27 carries a motor 29 on its upper side.

Sleeves 33 cover rods 34 which are attached at their upper ends to and depend from the platform, being connected at their lower ends to a cover plate 35 which forms a part of the sand receiving casing. having an opening 35 in one side thereof, as shown in Fig. 6, for the passage of sand from the receptacle 22 through said cover. Abracket 36 having two branches 36 is connected to and lies above the cover, being spaced at its intermediate portion a distance from the cover as shown. Suitable bearings one directly above the other are made in the brack-' et and in the coverplate 35 through which a hollow spindle 37 passes being provided at its lower end with conveying screw or helix 38. This lower portion of the spindle 37 with the attached conveyor screw 38' is housedwithin a housing 39 having an inner diameter but slightly larger than the diameter of the screw andhaving its upper end outwardly flared as shown in 39 and attached permanently to the cover. The hous-' ing member 39 is of cylindrical form and has a closing cap 40 connected thereto at its lower end which is of substantially semispherical form and provided with an outlet neck 41 in its lower portion to which a flexible tube 42 is connected, to serve as an outlet member to the sand casing. At the upper end of the screw 38 the spindle 37 is equi ped with a number of outwardly extending vanes 43 which are shaped to pass closely underneath the cover 35 and cut and scrape off sand which may be attempting to pass through the opening at .35 but which, on account of the necessary dampness of moulding sand, does not always move freely and is liable to pack together and resist movement. These vanes 43 serve to carry' the sand downwardly andinwardly to the casing 39 to below the screw and the lower end of the spindle 37.

To drive the spindle, a friction wheel 44 is attached thereto between the cover 35 and the bracket 36. Against this frictionwheel a drive pulley 45, s lined on a shaft 46, is adapted to bear and drive the same. The shaft 46 has a pulley 46' at its outer end around which a belt 46 driven by the motor 29, passes. The friction pulley may be moved away from the friction wheel, a ram 47 being attached thereto at one end and at its opposite end connected to a shaft 48 from which a handle 49 depends, the same being movable so as to either hold the pulley 45 in frictional contact with the wheel 44 or to carry said pulley out of contact there with.

In the lower end of the spindle 37 a nozzle member 50 is secured having a passage therethrough and, formed at its upper end with a valve seat. A tube 51 extends lengthwise of the spindle 37 being closed at its lower end by a cap 52. A conical valve 53 depends from a stem 54 which passes through the lower side of the cap 52 being provided with a head, as shown in Fig. 5, to prevent disengagement. A number of openings 55 are made in the tube 51 immediately above the cap 52.. Compressed air is supplied to the tube 51 through a pipe 56 which, through a suitable union 57, joint with the upper end of the tube 51 above. the spindle 37. In the position of the air tube and of the valve shown in Figs. 4 and 'side of the friction wheel 44.

neeasea the nozzle 50, and any sand which may be below this nozzle is forced through the neck 41 and the flexible conduit 42. y i

The union 57. has oppositely projecting pins 58 with which the forked end of a lever 59 engages, said lever being mounted on an eccentric 60 at its opposite end. The eccentric has a shaft 61 passing therethrough, 06 center, as shown in Fig. 3, and mounted in suitable vertical parts 36 on the divided'ends 36 of the bracket 36. The lever 59 is slotted between its ends as shown at 62. Through this slot a pin 63 carried by a block 64, passes, the block'being attached at the upper end of a rod 65 which extends downwardly through a suitable housing made in the bracket part 36, and has a forked member 66 at its lower end on which a roller 67 is mounted. A heavy coiled spring 68 under compression, is located in the housing between the upper side thereof and the fork 66., the-tendency of which is to move the tube 51 in a downward direction andbring'the valve 53 into engagement with the seat made in the up per end of the nozzle 50 and thus shut ed the passage of air through the nozzle mem her. The roller 67 bears against the upper A plurality of cams 69 are attached to the upper side of the friction wheel 44 so as to comeuhder the roller, elevating the same and attached parts. I have shown three of these cams in Fig. 6 though the number may be varied as desired. Whenever a cam runs under the roller the air tube 51 and attached valve 53 are elevated and the compressed air is permitted to escape through the nozzle 50. It is evident that in the operation of the machine there is a periodic change of position of the air tube 51 and that the air passes-through the nozzle 50 in successive jets which follow each other closely.

It will be noted that the valve 53 is not lifted off from the valve seat until the head of the stem .54 is directly engaged by the cap 52 to lift it. Normally the tendency is for the valve to seat firmly against its valve ressure of air against the.

seat due to the upper side of t e valve. The air cannot pass through the nozzle 50 until the valve is lifted from the seat and the time of passage of the air is governed by the distance that the valve is lifted. Accordingly, I have provided a means to control this by changing the position of the eccentric 60. Shaft 61 extends beyond the cover 35 and may be operated in any suitable manner by turning a vertically positioned rod or shaft 71 so as to turn the eccentric 60 to different positions and thereby give a greater or less range of movement to the end of the lever 59,'which is' connected to the air tube 51. An indicati pointer 72 may be connected to the shaft 1 passing over an indicating plate 73 to inform the operator as to the amount of. change he may make.

When the machine is in operation the sand is carried to the lower part of the easing being directed by the curved form of the end member 40 of the casing to immediately below the nozzle member. The pitch of the screw 38 is such that the sand will not pack but is carried downwardly and delivered in loose form to directly below the nozzle. The sand-thus delivered is acted upon by the jets of compressed air which pass from the nozzle directly against it, nnpelling the same through the neck 41 and the flexible conduit 42. There can be no large accumulation of sand below the nozzle as the jets of air come with great frequency and which may be controlled by the number of cams 69 which pass under the roller 67. The sand as it passes from the nozzle member 42 may be directed to any portion of aflask 74 located on a suitable support 75 under the lower end of the conduit 42. On this conduit a handle 76 is placed, preferably, so that the same may be bent to diflerent positions to direct the sand to any portion of the flask.

In Figs. 13 to 17 inclusive a construction is shown accomplishing the "same ends but with a simplified mechanism and for that reason preferred. The carriage which traverses the arms 18 may be modified so as to support a horizontal rod 77' lying parallel to the length ofthe arms and on which a yoke having depending spaced apart sides 78 is pivotally mounted. The pneumatic sand ramming mechanism is mounted be tween and at the lower ends of the arms 78, a rod 79 passing through just underneath the upper side 35 of the casing 39 of the machine, the mechanism being practically balanced on this rod. It is apparent that the universal movement of the mechanism is attained by this construction as well as by that previously described and in a sim er manner.

T e casing 39 is shorter than casing 39 and has an inletat its upper end and to one side for the'passage of sand thereinto from the hopper 22. The screw 38 is shorter and is connected to a spindle 37 which has. an opening through its entire length and which passes upwardly through the upper side 35 to the casing. The lower part of the casing 40 is modified slightly in that it is of. frusto-conical shape instead of semi-spherical as in the. first construction but it likewise hasa reduced neck 41 to which a flexible conduit 42 is connected.

The motor 29 for running the device is located at one side of the casing 39 and is connected with a vertical shaft 80 .by a clutch 81. The shaft passes upwardly throu h an extension to the cover 35 anu also t rough a plate 82 which covers the The clutch is operated by a handle 87 piv- 21c 90 is mounted.

otally mounted at 88 below the extension to the upper side of the casing, and from the shaft 88 a yoke 89 extends to engage with a suitable collar on the clutch whereby by operating the handle 87 the clutch may be disengaged when desired.

In the lower end of the spindle 37 a noz- Above the plate 82 a cam 91 is keyed to the spindle 37*. This spindle at its upper end is threaded above .the cam and on its threaded upper end a nut 92 is secured. A bracket 93 bent into the form shown inl igs. 13 and 15 is secured at one point to the plate 82 and is connected at its upper end bya rod 94 to the plate. Directly above the uppermost part of this bracket a valve casing 95 is positioned into which the compressed air conduit 56 leads. 'A short pipe 96 connects with the valve casing 95, passing through the bracket 93, and extends into the upper part of the nut 92 which-is interiorly bored and threaded for its reception. The lower end of the pipe 96 is enlarged to make a head and suitable packing is pressed above said head and secured in place by a nut 97 threaded into the nut 92 as shown in Fig.

15. This permits the free rotation of the spindle 37* while the pipe 96 remains stationary and without any loss of-alr at the connection.

A spring actuated valve 98 mounted on. a

rod 99 is located within the valve casing 95, the valve normally occupying aclosed .posi'tion v to prevent the passage of air through the valve casing and through the spindle 37*. Rod 99 projects beyond the valve -casing and at its end is engaged by a head 100 at the upper end of a lever 101 which is pivotally mounted at 102 on a suporting bracket 103. This 7 supporting racket 103 is adjustably mounted on the bracket 93 by means of a construction which will later be described. A horizontal rod 104 is mounted for longitudinal movements in the lower part of the bracket 93 and at one end is designed to bear against the cam 91. The lower end of the lever 101 is formed into a yoke to engage with a collar .105 fixed on rod 104 and the rod is norually pressed against the cam by a coiled spring 106 disposed between the collar and an upstanding portion of the bracket 93. It

, is evident when the spindle 37 is driven,

that rod 104 is twice ,reciprocated with the construction of cam 1 shown at, 91 in Fig. 16. The movement or reciprocation of the rod, however, may be readily controlled with different designs of cams having a greater or less number' of pro-. jections for operating the rod. \Vith every reciprocation of the rod lever 101 is oscillated about its pivot 102 and the valve 98 first opened and then allowed to close, this permitting periodical passage of compressed air downwardly through the spindle and out of the nozzle at 90, as is obvious.

The bracket 103 passes through a slot in bracket 93 back and at each side of which members 107 are secured. A shaft 108 passes through the bracket 103 and between the members 107 and the bracket 93 whereby bracket 103 is pivotally mounted on the shaft 108. A shaft 109 is located above shaft 108 and mounted at its ends in the members 107. The bracket 103 is slotted for the passage of this shaft and for the reception of an eccentric 110 mounted on or formed integral with the shaft 109. At one end the shaft 109 extends beyond the adja-' of the com ressed air in this way con- 'trolled. Ad acent the lower end of rod 112 a pointer v113 is fixed, the same being adapted to pass over an indicating scale 114, serving to guide the operator in adjusting the air. The motor clutch, plate 82 and the mechanism located above thefisal'ne are all covered preferably, by a sheet metal cover 115 so as .to preclude the entrance of sand, dust or the like which would be injurious to the mechanism.

This construction of mechanism is simpler than that previously described and with it the same results are attained. The compressed air acts periodically, passing from.

ment may be attained; and inaddition the flexible outlet tube or conduit 42 may be turned to different positions so that the sand may be directed wherever desired. In both constructions the sand is carried in loose form to below the screw and is more or less. packed between the lower turn of the screw and the end or 40 of-the casing, makin a seal whichprevents the blowing of san in an. upward direction in the casing and escape of air in that'direction, the sand being forced outthrou h the reduced portion 41 at the lower en of the casing. Various changes in minor detail of construction may be resorted to without departing-from .the-

' lower end, a vertical spindle extending downward into the casing and mounted for rotation on the cover, means to' drive the spindle, a conveying screw on the spindle, said screw car ing the sand in losse:form to the lower en of the casi and below the lower end of the spindle, an means to automatically deliver compressed air at periodic intervals from the lower end of the spindle against the sand below said spindle to project the sand out of the casing through the outlet, substantially as described.

2. In combination, a sup rt including a horizontal supporting mem er, a carriage mounted to move back and forth thereon, a casin suspended from the carriage and mounte thereon to have pivotal movement about two horizontal axes located at right angles to each other, means rotatably mounted within the casing for carrying sand entered into the casing at its u per endto' the lower end of the casing, an means for periodically ejecting said sand fromthe casmg at the lower end thereof, substantially as described.

3. In combination, pneumatic means for projectingsand in small quantities and in quick succession into a mouldin flask, and means for dellvermg sand to em pneumatlc means, substantially as described.

4. ln'combination, a sand receiving casin having a cover for the upper end thereo said cover having an. inlet opening therethrough, a spindle mounted to turn on a vertical axis and extending through the cover into the casing, a conveying screw on the spindle for carrying sand to the lower art of the casing, means on the spindle a ove the screw and below the cover for carryin sand entered into the casing through sai inlet 0 ening to the screw, means to rotate the spindle, and means to periodically deliver comdpress'ed air from the lower end of the spin le against sand which has been recast said lower portion of the casing being provided with an outlet through, which the sand may beejected by the air, substantially as described.

5. lncombination, a sand receiving and carried to the lower portion of the casing,

the mec anism back and forth in a horizontal plane, means for swinging the mechanism back and forth about either of two horizontal axs located a distance above the mechanism, said mechanism having an outlet thereto and a nozzle attached to the outlet adapted to swing to any desired angle with respect to the outlet, substantially as described 7. In combination, .a support, a sand receiving and ejecting mechanism suspended from and movable back and forth on the support, means for delivering sand. to the mechanism, means included in the mechanism for continuously carrying the sand delivered thereto to a lower position in the mechanism, and pneumatic means for acting on the sand at close intervals to eject the sand in small quantities into a moulding flask, substantially as and for the purposes described.

v8. In combination, a support, a casing movably mountedon the support and depending below the same, said casing having an entrance opening in the upper part for 9. In combination, a casing having an upper inlet opening and a lower outlet, a spindle passing through the casing at the upper end thereof, sa1d s' indle having an.

opening extending its entire length, a conveying screw at the lower end of the spindle, means for driving the spindle, a conduit, a valve located therein above the upper end of the spindle, means for connecting 4 said conduit and spindle, means for carryi ing air under pressure to the valve, and means for opening the valve at intervals with the rotation of the spindle to permit the passage of air through the valve and through the spindle to the lower end thereof, substantially as described.

10. In combination, a hollow casing having an upper inlet opening and a lower outlet, a spindle passing through the upper side of the casing and extending downwardly into the casing, said spindle having an opening throu hout its length, a conveying screw on the ower part of the spindle, a motor, gearing mounted. on the upper side' of the casing driven by the motor for thereby turning the spindle, a plate covering the gearing, means to conduct compressed air to the upper end of the spindle, a normally closed valve interposed in the length of said means for stopping the passage of air, and means operated by the rotation of the spindle for opening the valve at intervals to permit the passage of air therethrough and through the spindle to a point below the lower end thereof, substantially as described.

11. In combination, a hollow casing having an upper inlet opening and a lower outlet thereto, a spindle mounted in the casing and extending above the same, a con.- veying screw on the spindle, said spindle having an opening throughout its entire length, a cam on the spindle, a conduit for carrying compressed air to the upper end of the spindle, a normally closed valve 10- cated in the length of the conduit. and means operated by movement of the cam as the spindle turns for opening the valve to permit the passage of air through the spindle and out at the lower end thereof, substantially as described.

12. In combination, a casing having an upper inlet opening and a lower outlet thereto, a spindle mounted vertically in the casing, a conveying screw on the spindle between said inlet opening and outlet, said spindle having a longitudinal opening therethrough, a conduit for carrying compressed air to the lupper end of the spindle, a normally closed valve located in the length of the conduit, a cam on the spindle, means to,

drive the spindle, means operated by the cam for opening the valve at intervals,- and means to adjust said cam operating means to difi'erent positions to govern the extent that the valve is opened, substantially as and for the purposes described.

13. In combination, a casing provided with an upper inlet opening and with an outlet thereto, a spindle passing through the upper side of and extending a distance into the casing, a. conveying screw on the spindle between the inlet and outlet to the casing, a gearing on the spindle above the upper side of the casing, a motor located alongside of the casing, gearing connections between the motor and the gear on the spindle for continuously driving the spindle, a plate covering the gears, a cam mounted on the spindle above the plate, a conduit for carrying compressed air to the upper end of the spindle, said spindle having an opening through its entire length, a normally closed ,valve mounted in the conduit, a bracket mounted on the plate, a lever pivotally mounted between its ends on the bracket, a rod attached to the valve and projecting outwardly into engagement with the lever, and means operated by the cam for turning the lever about its pivot to thereby open the valve to permit the passage of air through the spindle, substantially as described.

14. In combination, a casing having an upper inlet and lower outlet thereto, a spindle mounted vertically in the casing and extending above the same, a conveying screw on the lower partpf the spindle, a conduit for carrying air under compression to the upper end of the spindle, said spindle having a longitudinal opening through its entire length, a normally closed valve in said conduit, means for continuously driving the spindle in one direction, means operated by the spindle for opening the valve at intervals, and means for controlling the extent that the valve shall open, substantially as and for the purposes described. 15. In combination, a casing having an upper inlet opening and a lower outlet thereto, a mechanism mounted on the casing for periodically projecting sand in small quantities from the casing through the lower outlet thereto, a yoke on which said casing is mounted to turn about a horizontal axis, and" means for mounting the yoke to turn about a horizontal axis located at right angles to the-axis on which the casing is mounted, substantially as described.

16. In combination, a casing having an upper inlet and a lower outlet thereto, a spindle having an opening throughout its entire length mounted vertically in the casing and extending above the same, means for turning the spindle, a conve ing screw on the bracket, spring means acting to force said second rod against the cam. a second bracket mounted on the first bracket, means to adjust the second bracket to different positions, and a lever pivotally mounted between its ends on the second bracket and rod and connected at its lower end to the second mentioned rod, substantially as and .for 5 1 flask in molding,

ing

b I Pi the purposes described.

7. The process of supplying sand to a which comprises impactit in said flask and about the pattern application of compressed air with exsive effect.

18. An apparatus for supplying sand to molding flasks, comprising means for containing a charge of sand, and fluid pressure means for suddenly applying fluid pressure behind said charge and ejecting it bodily intoisaid flask with impacting force.

In testimony whereof I aflix my signature.

DONALD J. CAMPBELL. 

